A new convenient route to radioiodinated N-succinimidyl 3- and 4-iodobenzoate, two reagents for radioiodination of proteins

A straightforward method for the synthesis of N-succinimidyl 3- and 4-[124I]iodobenzoate (m- and p-[124I]SIB) via destannylation has been developed. The stannylated precursor was obtained as a white crystalline solid in 80% overall yield from 3- or 4-iodobenzoic acid after a two step synthesis. Iododestannylation was performed with 4.2-d (25% β+)124I and Iodogen or Iodobeads as the oxidant yielding 90% of the desired product.